Final answer:
The total amount of drywall required for the ceiling and walls of an 8ft x 10ft x 20ft room is 560 square feet. This is calculated by adding the area of the ceiling (80 square feet) to the total area of the walls (480 square feet).
Step-by-step explanation:
To calculate the amount of drywall needed for the ceiling and walls of an 8ft x 10ft x 20ft room, you need to find the surface area of the room. The total surface area includes the area of the ceiling and the four walls. The ceiling's area is length x width (8ft x 10ft = 80 square feet).
Each wall's area can be calculated as height x length or height x width. Therefore, two walls would have the area 8ft (height) x 20ft (length) = 160 square feet each and two walls would have the area 8ft (height) x 10ft (width) = 80 square feet each.
The total area of the walls is therefore 2 x 160 + 2 x 80 = 480 square feet. Adding this to the area of the ceiling (80 square feet), we get a total of 560 square feet of drywall required.
Learn more about Surface Area